Michel M. Maharbiz (Advisor)

Research Advised by Professor Michel M. Maharbiz

BPN478: Synthetic Microbial Pattern Formation Modulated by a Chemical Micro-interface

Taesung Kim

We develop a technique for producing synthetic microbial patterns by means of direct activation and inactivation of gene expression in an initially homogenous population of cells using a microfluidic chemical interface system. A strain of E. coli was engineered such that the presence of the membrane diffusible molecule acyl-homoserine lactone (AHL) activates the production of more AHL, thereby creating a positive feedback loop. Since the half-life of AHL decreases in high pH solutions, this feedback loop can be inhibited in a specific area by modulating the local pH using a...

BPN450: A Microsystem for Sensing and Patterning Oxidative Microgradients During Cell Culture

Jaehyun Park

We present a microsystem capable of electrochemically patterning dissolved oxygen gradients during cell cultures. Multiple electrodes in an array each generate distinct amounts of dissolved oxygen via electrolysis; these different sources superimpose to generate one- and two-dimensional microgradient profiles not possible with other methods. We believe this is the first technology that enables researchers to pattern localized oxygen doses and program arbitrary oxygen gradients with microscale resolution during cell culture.

Project end date: 02/03/10

BPN500: Inkjet Interfaces for Controlling Biological Pattern Formation

Daniel Cohen

We have successfully adapted a consumer-grade inkjet printer for use as a means of controlling spatio-temporal gene expression in 2D cell culture. Specifically, we take advantage of a high-resolution printer designed to print on the surface of CDs. By modifying CD surfaces to contain customized Petri dish wells, we are able to culture E. coli in the wells and print various morphogens onto the surface of the culture. By varying the geometry of printed patterns of lactose and glucose we have demonstrated spatiotemporal control over the genetic activity of the lac operon. Having...

BPN521: Passive Wireless Transducers for a Distributed High Density Neural Interface

Peter Ledochowitsch

In this project we are striving to develop biocompatible passive micro-scale transducers which are able to measure transient extracellular ion concentrations and transmit them at microwave frequencies. We are interested in fabricating implantable MEMS devices which shift their resonant frequency whenever a nearby neuron fires. When implanted up to 2 mm deep into the brain cortex, we expect these devices to enable next-generation distributed neural interfaces featuring not only superior spatial and temporal resolution of extracellular action potentials but also robust long-term...

BPN553: Interactive Materials for Biofabrication

Daniel J. Cohen

Nearly all medical implants and tissue engineered structures (i.e. lab-grown organs) are implanted or grown in a manner where it is difficult to non-destructively assess performance or progress and to make adjustments on the fly. For instance, suppose we wish to engineer a vascular graft to repair a damaged coronary blood vessel. In this case, we would start by taking a scaffold material shaped like a blood vessel and then coating it with endothelial and smooth muscle cells. We would then 'grow' the structure in a bioreactor for a fixed period of time and then implant it into the...

BPN610: Measuring Contractile Force in Engineered Muscle via Percolation Strain Gauges

Daniel J. Cohen

The Technology: I am developing a new kind of piezoresistive strain sensor capable of sustaining strains up to at least 25% and with a gauge factor far greater than that found in traditional resistive gauges. The sensor is designed as an elastomer-nanotube composite that deliberately avoids the major failure modes of traditional resistive strain gauges. In addition to improved elasticity and sensitivity, this type of sensor can be shaped into nearly any configuration and embedded in a variety of polymers. These attributes are particular important given that the application is to...

BPN451: A Cyborg Beetle: Insect Flight Control by a Neural Stimulator

Hirotaka Sato
Travis L. Massey

Despite major advances, performance of micro air vehicles (MAV's) is still limited in terms of size, payload capacity, endurance, and controllability. Various species of insects have as-yet unmatched flight capabilities and increasingly well understood muscular and nervous systems. Additionally, some of these insects undergo complete metamorphosis making them amenable to implantation and internal manipulation during metamorphosis. In light of this, we attempt to create implantable bio-interface to electrically stimulate nervous and muscular systems of alive insect to control its...

BPN545: Brain Machine Interfaces for Insect Flight Control

Amol Jadhav

Insects with well developed flight muscles and sophisticated neuronal network signify nature's amazing flying machines which far surpass any human engineered initiative at this scale (e.g. micro air vehicles). The complicated mechanism of flight involving generation of flight response in the brain and delegation of control spikes to the flight muscles remains relatively unexplored and presents opportunity for advanced tools and techniques to further explore this area. In this project we intend to use advanced Brain Computer Interfaces (BCI) to perform neuronal ensemble measurements...

BPN626: Glucose Energy Harvester for Self-Powering of Remote Distributed Bioanalytical Microsystems

Uyen P. Do

This project focuses on the research aspects concerning the harvesting of energy from glucose in order to power autonomous, self-sustainable MEMS implants by the aid of an abiotically catalyzed micro fuel cell. The results will demonstrate a novel fuel cell architecture that first separates the oxygen at the cathode from the glucose – oxygen mixture present in the body fluid with the aid of diffusion and the use of an oxygen selective catalyst at the cathode. The in vitro prototypes will demonstrate the energy conversion from chemically stored energy (glucose) to electrical energy...

BPN496: Chemomechanical Nanomachine for Artificial Biomolecular Signal Transduction and Drug Delivery

Gabriel J. Lavella

We have developed a class of nanomachine that can rationally designed to chemomechanicaly respond to user specified antigenic biomolecules. Our long term goal is to demonstrate that these devices can be employed to achieve highly localized controlled of the cell signaling network.

Project end date: 08/16/12